A surgical mask is a loose-fitting, disposable device that creates a physical barrier between the mouth and nose of the wearer and potential contaminants in the immediate environment. Medical masks are made to be fluid resistant, with the waterproof layer on the outside to minimize the amount of fluid that could transfer from the outer layers through to the inner layers as the result of a splash or spray. They are designed to filter ≥95% of particulates.
These are often referred to as face masks, although not all face masks are regulated as medical masks. Note that the edges of the mask are not designed to form a seal around the nose and mouth.